Rate constants for the reactions of Cl atoms with HCOOH and with HOCO radicals

Rate constants have been measured at room temperature for the reactions of Cl atoms with formic acid and with the HOCO radical: (R1) Cl + HCOOH --> HCl + HOCO (R2) Cl + HOCO --> HCl + CO2 Cl atoms were generated by flash photolysis of Cl-2 and the progress of reaction was followed by time-resolved infrared absorption measurements using tunable diode lasers on the CO2 that was formed either in the pair of reactions (R1) plus (R2), or in reaction (R1) followed by (R3) O-2 + HOCO --> HO2 + CO2 In a separate series of experiments, conditions were chosen so that the kinetics of CO2 formation were dominated either by the rate of reaction (R1) or by that of reactions (R1) and (R2) combined. The results of our analysis of these experiments yielded: k(1) = (1.8(3) +/- 0.12) x 10(-13) cm(3) molecule(-1) s(-1) k(2) = (4.8 +/- 1.0) x 10(-11) cm(3) molecule(-1) s(-1) (C) 2000 John Wiley & Sons, Inc.